Responses
I think in Bums point of view he even believes that homosexuality is wrong/disgusting and that's why he's so glad that Sangwoo is in love with him (in Bum's world at least). His dependence on Sangwoo is impressive and so tragic. Bum needs to know that 1) homosexuality is fine, 2) he deserves better than Sangwoo and 3) that he's a human being worth of respect and confidence.
(lol also 4) don't stalk your crush)

He did stuff with Bum that no one else would. So I think that justifies why Bum fell in love with him ultimately which in the ends results in him defending Sangwoo till the end despite us all hatin on Sangwoo.
This chapter was really an eye opener, like Bum is so right, Officer Yang would not have done that kind of stuff with Bum, but Sangwoo did, but I'm also not saying that Sangwoo is in no way a villain.
If this ends where Bum defends Sangwoo because Bum does it out of true love regardless of past events, I think I will be satisfied because in the end...
It will show that true love defies all stereotypes and odds, he did in the name of love although it was totally unjust. (Almost like the JokerxHarley thing where Joker is so bada$$ but Harley still loves him regardless) ┗( T﹏T )┛